jonah peretti, co-founder of "the huffington post," was so impressed when he received one, he became an individualer and mentor to the pair. >> what the company has found is people are receivers first. they get a few, i keep getting these beautiful invitations and it's usually from a friend of mine who's a high-status friend, a person that i respect. maybe i should go and use the service. then they come and use the service, it spreads that way. >> reporter: more affordable than people stationery, environmentally friendly, and fast, paperless post attracted high-profile users and institutions like prince charles, condoleezza rice, the museum of modern art, and the white house. >> the website is simple to use. it's nice to send something that is going to reflect all the effort and energy you put into the party. >> reporter: with 50 million invitations sent and a service that is low-cost, everyone is taking notice, even the industry's largest player. e-vite recently launched postmark, a site remarkably similar. >> there's a lot of examples of big companies trying to copy what the nimble